Death is the end of life: anything that lives must die at one point (otherwise, it isn't living !) Death is a normal thing, that ends all lives, even though many ones don't want their life to end : this is why many fear the death.

Death may occur when getting old, as the body weaken and can't continue to live, or by "accident": one may be killed by something, like a disease, or a serious wound, for example.